Journal of Natural Products

dx.doi.org/10.1021/np3007827|

Cryptocapsinepoxide-type Carotenoids from Red Mamey,

Pouteria sapota

Gergely Gulyás-Fekete,† Enrique Murillo,‡ Tibor Kurtán,§ Tamás Papp,§ Tünde-Zita Illyés,§

László Drahos,┴ Júlia Visy,║ Attila Agócs,† Erika Turcsi,† and József Deli†,*

†Department of Biochemistry and Medical Chemistry, Medical School, University of Pécs,

Szigeti út 12, 7624, Pécs, Hungary, ‡Department of Biochemistry, Faculty of Exact Natural Sciences and Technology, University

of Panama, Panama City, Panama, §Department of Organic Chemistry, Faculty of Sciences, University of Debrecen, Egyetem tér

1, 4032 Debrecen, Hungary┴ Institute of Organic Chemistry, Research Centre for Natural Sciences,

Hungarian Academy of Sciences, Pusztaszeri út 59-67, 1025 Budapest, Hungary║ Institute of Molecular Pharmacology, Research Centre for Natural Sciences,

Hungarian Academy of Sciences, Pusztaszeri út 59-67, 1025 Budapest, Hungary

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ABSTRACT

Three new carotenoids, cryptocapsin-5,6-epoxide, 3ʹ-deoxycapsanthin-5,6-epoxide, and

cryptocapsin-5,8-epoxides, have been isolated from the ripe fruits of red mamey (Pouteria

sapota). Cryptocapsin-5,6-epoxide was prepared by partial synthesis via epoxidation of

cryptocapsin and the (5R,6S)- and (5S,6R)-stereoisomers were identified by HPLC-ECD

analysis. Spectroscopic data of the natural (anti) and semisynthetic (syn) derivatives obtained

by acid-catalyzed rearrangement of cryptocapsin-5,8-epoxide stereoisomers were compared

for structural elucidation. Chiral HPLC separation of natural and semisynthetic samples of

cryptocapsin-5,8-epoxides was performed and HPLC-ECD analysis allowed configurational

assignment of the separated stereoisomers.

Carotenoids containing a -end group such as capsanthin (1), capsorubin (2), and

cryptocapsin (3) occur mainly in red paprika (Capsicum annuum).1-3 Capsanthin (1) has also

been found in the pollen anthers of Lilium tigrinum,4,5 in the fruit of Berberis spp.,6 as well as

Asparagus officinalis.7,8 Capsorubin (2) has also been isolated from the integument of

Encephalartos altensteinil, petals of Cajophora lateritia,9 and the fruits of A. officinalis.7,8

Earlier we reported the isolation and characterization of a range of carotenoids with a -end

group from red paprika including capsanthin-5,6-epoxide,10 capsanthin-3,6-epoxide,10,11 5,6-

diepicapsokarpoxanthin,5,12 and capsoneoxanthin,13 which contained 5,6-epoxy-, 3,6-epoxy-,

3,5,6-trihydroxy- and allenic end groups, respectively. While the -ring is hydroxylated in

these carotenoids, Maoka and his co-workers14 have identified two carotenoids with a non-

hydroxylated -ring from red paprika. A survey of local plants in Panama has revealed the

presence of ketocarotenoids in a range of species. Plants with high concentrations of

ketocarotenoids have been reported in fruits such as 'mamey' (Pouteria sapota), 'maracuya

chino' (Cionosicyos macranthus), 'jipijapa' (Carludovica palmata), and in young red-brown

leaves and red seeds of Zamia dressleri.15

We have reported the isolation of sapotexanthin [(5R)-,-caroten-6-one, (4)],16 3ʹ-

deoxycapsorubin, and 3,3ʹ-dideoxycapsorubin,17 from the panamian fruit mamey (Pouteria

sapota), which are carotenoids with non-hydroxylated -end groups. The structural

elucidation of these carotenoids was accomplished by MS, electronic circular dichroism

(ECD), and NMR methods.16,17 It was also established that the mamey fruit contains several

carotenoids with a -end group including cryptocapsin (3) as the main carotenoid

component.18

Herein, the isolation of the new carotenoids cryptocapsin-5,6-epoxide (5), 3ʹ-

deoxycapsanthin-5,6-epoxide (6), and cryptocapsin-5,8-epoxides (11, 12) is reported from the

fruits of red mamey. Cryptocapsin-5,6-epoxide (5) was prepared by the epoxidation of

cryptocapsin (3) as a reference compound. Spectroscopic data of natural (anti, 5) and

semisynthetic (syn, 7) compounds were analyzed for structural elucidation.

RESULTS AND DISCUSSION

Red mamey was extracted according to published procedures.16 Repeated column

chromatography of the mamey extract on Al2O3 and CaCO3 yielded 8 mg cryptocapsin (3), 4

mg cryptocapsin-5,6-epoxide (5), 0.5 mg 3ʹ-deoxycapsanthin-5,6-epoxide (6), 0.5 mg -

cryptoxanthin-5,6,5ʹ,6ʹ-diepoxide (8), and 1.5 mg of an epimeric mixture of cryptocapsin-5,8-

epoxides (11, 12).

Structure Elucidation of the Natural Cryptocapsin-5,6-epoxide (5)

The structure of cryptocapsin-5,6-epoxide (5) was established from its UV-VIS, ECD, MS,

and 1H and 13C-NMR data. The UV-VIS spectrum (max: 480 and 505sh nm in benzene) was

in agreement with a decaene chromophore containing a conjugated carbonyl group. Reduction

of cryptocapsin-5,6-epoxide (5) with NaBH4 gave an approximately 1:1 mixture of the

corresponding stereoisomeric alcohols. The UV-VIS spectrum of this mixture exhibited well-

defined fine structure and a hypsochromic shift (max: 426, 451, 481 nm in benzene). Upon

treatment with HCl/HOAc, the 464, 486 nm max value of the resultant product indicated the

presence of a 5,6-epoxy group. The HPLC-MS and HRESITOFMS of 5 showed a molecular

ion at m/z 584.4241, which corresponds to the formula C40H56O3. Owing to the rapid

rearrangement of the 5,6-epoxy to the 5,8-epoxy group during NMR experiments, 1H,1H-

COSY and 13C NMR data could not be recorded. Thus, NMR analysis was restricted to the

protons of the end-groups in 5. The 1H NMR chemical shifts of 5 were compared with those

of semisynthetic-cryptoxanthin-5ʹ,6ʹ-epoxide19 (9) and capsanthin-5,6-epoxide20 (10). 1H

NMR experiments of 5 revealed the presence of a 5,6-epoxy- end group, a 3-hydroxy-6-oxo-

end group, and an all-E polyene chain. Because the NMR data of the syn and anti epoxides

are identical, the assignments are only given for the semisynthetic compound. Since the

diastereomers with non-hydroxylated (5R,6S) or (5S,6R)-5,6-epoxy-end groups cannot be

distinguished by their 1H NMR spectra, the configurational assignment of the cyclohexane

ring was based on chiroptical data.

The ECD spectra of carotenoid-5,6-epoxides are governed by the configuration of C-5 and C-

6, and additional substituents of the -end group have no significant influence on the ECD

transitions. The influence of the additional -end group on the ECD spectra is also rather

small, and hence the absolute configuration of the 5,6-epoxy group could be determined

unambiguously.21 The natural cryptocapsin 5,6-epoxide (5) gave positive Cotton effects (CEs)

at 207, 242 and 349 nm and negative ones at 215 and 281 nm, which is in agreement with the

ECD data of natural capsanthin-(3S,5R,6S)-5,6-epoxide (10).20 Consequently, the ECD

spectra confirmed the (5R,6S) configuration of natural cryptocapsin-5,6-epoxide (5) (Figure

1).

Epoxidation of Cryptocapsin (3)

In order to characterize the natural cryptocapsin-5,6-epoxide (5), it was synthesized from

cryptocapsin (3) by epoxidation with monoperoxophthalic acid. The epoxidation produced

two diastereomeric 5,6-epoxides with (5R,6S) and (5S,6R) absolute configurations.19,20 The

separation of such diasteromeric epoxides with unsubstituted -ring is usually not considered

straightforward. However, in our case, base-line separation of (5R,6S)- and (5S,6R)-

cryptocapsin-5,6-epoxide diastereomers (5 and 7, respectively) was achieved on a Chiralcel

OD HPLC column, which showed ca. equal amounts of the two diasteromers (Figure 2).

The OR-detected HPLC chromatogram showed that both diastereomers had positive optical

rotation and hence this optical parameter was not suitable to distinguish them. Since online

HPLC-ECD measurements had been shown an efficient tool for studying stereoisomeric

mixtures of natural products,22-24 this technique was employed in separation of diastereomers 5

and 7. The HPLC-ECD chromatogram (Figure 2a, upper curve) recorded at 280 nm showed

opposite CEs for the two diastereomers. Online HPLC-ECD spectra were recorded by

stopping the flow of the eluent in the HPLC-ECD flow cell at the maximum concentration of

the separated diastereomers. The diastereomers had near mirror image ECD curves above 250

nm allowing the configurational assignment of the synthetic diastereomers (Figure 3).

The CEs of natural (anti, 5) and semisynthetic (syn, 7) cryptocapsin 5,6-epoxides had

opposite signs above 250 nm reflecting the different configuration of the 5,6-epoxy-end

groups. These data corroborated well the reported values of anti and syn-capsanthin-5,6-

epoxide.20 1D and 2D NMR analysis was also performed for the diastereomeric mixture of

(5R,6S)- and (5S,6R)-cryptocapsin-5,6-epoxides 5 and 7. The 1H and 13C signals were

assigned by means of 2D 1H COSY, 13C HSQC and 13C HMBC spectra. The proton chemical

shifts of the end groups (H-7 at 5.90 ppm, H-8 at 6.29 ppm) and the 3JH,H coupling

constants (J7,8 = 15.4 Hz) were identical with the corresponding data of the natural (5R,6S)

cryptocapsin-5,6-epoxide (5). HSQC experiments revealed the presence of 5,6-epoxy- and 3-

hydroxy-6-oxo- end groups, since H-3ʹ resonated at 4.51 ppm as a multiplet and C-3ʹ at 70.4

ppm.25

Structure Elucidation of 3ʹ-Deoxycapsanthin-5,6-epoxide (6)

The 3ʹ-deoxycapsanthin-5,6-epoxide (6) showed a similar UV-VIS spectrum to that of

cryptocapsin-5,6-epoxide (5) [max: 480 and 505(sh) nm in benzene, which is shifted to 464,

486 nm after acid treatment in benzene]. The HRESITOFMS exhibited a parent ion at m/z

584.4232, which corresponded to the formula C40H56O3. Owing to the small amount of sample

available, this compound was characterized only by 1H NMR. 1H chemical shifts of the end

groups and 3JH,H coupling constants were compared with those of sapotexanthin16 (4) and

capsanthin-5,6-epoxide (10),20 confirming the proposed structure. The proton signal at 3.93

and 3JH,H values of the 3-hydroxy--end group were identical with the corresponding literature

data.19,20 These data indicated that the hydroxy group is attached to the cyclohexane ring

(3.93 for H-3).25 The 1H signals of the 14 olefinic protons were only partially assigned. The

ECD spectrum of 3´-deoxycapsanthin-5,6-epoxide (6) showed positive CEs at 240 and 347

nm and negative ones at 214 and 280 nm, which were in agreement with the ECD data of

natural capsanthin-5,6-epoxide.20 Thus, the ECD spectrum confirmed the (5R,6S) absolute

configuration of 6 (Figure 1). Based on the NMR and ECD data, 6 was identified as (all-

E,3S,5R,6S,5ʹR)-3-hydroxy-,-caroten-6ʹ-one, for which the 3ʹ-deoxycapsanthin-5,6-epoxide

trivial name is proposed.

Structural Elucidation of -Cryptoxanthin-5,6,5ʹ,6ʹ-diepoxide (8)

In the UV-VIS spectra of 8, the 428, 453, and 483 nm maxima in benzene and the fine

structures were in accordance with the reported data for -cryptoxanthin-5,6,5ʹ,6ʹ-diepoxide.19

On acidic treatment, 8 underwent furanoid rearrangement and the rearranged product had

characteristic absorption maxima at 388, 410, 436 nm in benzene. The identification of 8 was

based on comparison with NMR data published by our group for the corresponding 5,6-epoxy

end groups.19 The ECD spectrum of 8 was similar to that of the reported spectrum,19 hence

confirming the (3R,5R,6S,5ʹR,6ʹS) absolute configuration (Figure 1).

Structural Elucidation of Cryptocapsin-5,8-epoxides (11, 12)

The UV-VIS spectrum of the mixture of 11 and 12 (max: 464 and 486 nm in benzene) was in

agreement with a nonaene chromophore containing a conjugated carbonyl group. The HPLC-

MS exhibited a parent ion signal at m/z 584.42, which corresponded to a molecular formula of

C40H56O3. The HPLC analysis of this compound showed two peaks with identical UV-VIS

spectra indicating the presence of two stereoisomers with (5R,8S) and (5R,8R) absolute

configuration. However, these stereoisomers could not be separated by column

chromatography using a CaCO3 stationary phase. The proton chemical shifts and coupling

constants, and 13C chemical shifts of the 5,8-epoxy--end group were identical with the

reported data.25,26 Pairs of doublets appearing at 5.16 and 5.24 ppm (H-7) as well as at 5.18

and 5.08 ppm (H-8) confirmed the presence of the two stereoisomers with ~2 : 1 ratio. The 1H

and 13C chemical shift values of H-8 and C-7 of the -end group of 11 and 12 were different,

which suggested different configuration of C-8. Owing to their complexity, the 13C NMR

signals of 11 and 12 were only partially assigned and 13C NMR data could not be obtained for

the quaternary carbons.

The base-line separation of 11 and 12 was achieved on a Chiralpak IC column. The UV

chromatogram showed that the two epoxides had a 1:1.8 ratio (Figure 4). Since the amount of

sample was not sufficient for multiple injections and online HPLC-ECD analysis, the

authentic samples of 11 and 12 had to be synthesized. This was accomplished by acid-

catalyzed rearrangement of the stereoisomeric mixture of cryptocapsin-5,6-epoxides 5 and 7,

which afforded a stereoisomeric mixture of cryptocapsin-5,8-epoxides (11-14). A base-line

HPLC separation of the resulting four stereoisomeric cryptocapsin-5,8-epoxides (11-14) was

achieved on a Chiralpak IC column (Figure 4) using the same HPLC conditions that were

developed for the separation of (5R,8S)-11 and (5R,8R)-12. The HPLC analysis of synthetic

epoxides showed a 1:2.7:1.1:2.3 ratio of the stereoisomers. Comparison of the HPLC profiles

of natural and synthetic cryptocapsin-5,8-epoxides permitted the identification of synthetic

(5R,8S)-11 and (5R,8R)-12 as the the first- and fourth-eluting stereoisomers, respectively. The

absolute configurations of 11 and 12 were assigned on the basis of their online HPLC-ECD

spectra. On the basis of reported ECD data of natural (5R,6S)-cryptocapsin 5,6-epoxide (5),27

the (5R) absolute configuration was assigned for both 11 and 12. Moreover, the onle HPLC-

ECD spectra of 11 and 12 showed opposite CEs at 204 and 267 nm, which suggested (5R,8S)

absolute configuration for the first-eluting stereoisomer [(5R,8S)-11] and (5R,8R) for the

fourth-eluting one [(5R,8R)-12] in accordance with the literature data of furanoid

derivatives.28 The second-eluting stereoisomers 13 and the third-eluting 14 had (5S) absolute

configuration, and hence they were identified as (5S,8R)-13 and (5S,8S)-14 (Fig. 5).

Biosynthesis

The formation of 3-hydroxy--end group from a 3-hydroxy-5,6-epoxy--end group by

pinacol rearrangement is a well known biosynthetic route.29 Capsanthin (1), capsorubin (2),

and cryptocapsin (3) are formed by this transformation from antheraxanthin, violaxanthin, and

-cryptoxanthin-5,6-epoxide, respectively.2 Carotenoids possessing a 5,6-epoxy functional

group in their hydroxylated -rings are quite common in nature. However, carotenoids with

5,6-epoxy groups in a non-hydroxylated -ring have been rarely reported. In the red mamey,

the presence of carotenoids containing no hydroxylated -rings can be attributed to the

coincidence of two rare metabolic events: 1) high activity of enzymes catalyzing the

epoxidation of non-hydroxylated -rings and 2) enzyme-catalyzed pinacol rearrangement of

epoxides. The high concentration of -cryptoxanthin-5,6,5ʹ,6ʹ-diepoxide (8) that contains

hydroxylated and non-hydroxylated 5,6-epoxy--rings facilitates the formation of

cryptocapsin-5,6-epoxide (5) and 3´-deoxycapsanthin-5,6-epoxide (6) (Scheme 1).

EXPERIMENTAL SECTION

General Experimental Procedures: The UV-VIS spectra were recorded with a Jasco

V-530 spectrophotometer in benzene. The exact mass measurements (HRESITOFMS) were

performed using a Waters Q-TOF Premier mass spectrometer (Waters Corporation, 34 Maple

St, Milford, MA, USA). The sample was dissolved in MeOH and measured in positive

electrospray ionization mode.

The 1H (400 MHz) and 13C NMR (100 MHz) spectra were measured with a Varian UNITY

INOVA 400-WB spectrometer and on a Bruker DRX Avance II (500/125 MHz for 1H/13C)

spectrometer. Chemical shifts are referenced to internal TMS (1H), or to the residual solvent

signals (13C). ECD spectra were recorded at room temperature with a J-810

spectropolarimeter.

HPLC-DAD Analysis: The HPLC system was interfaced into gradient pump Dionex

P680, equipped with a Dionex PDA-100 detector and the data were processed by Chromeleon

6.70 software. The HPLC separations were carried out on an endcapped C30 column (250 x

4.6 mm i.d.; YMC C30, 5µm). The eluents consisted of (A) MeOH : MTBE : H2O = 81 : 15 :

4 and (B) MeOH : MTBE : H2O = 6 : 90 : 4. The chromatographic separation were carried out

using a linear gradient consisting of 100% eluent A at time zero that was changed to 50%

eluent B within 45 minute at a flow rate of 1 mL/min.

Chiral HPLC and HPLC-ECD Analysis: Chiral HPLC separations were carried out with a

Jasco HPLC system on Chiralcel OD column (0.46 cm 25 cm, 5 m) using n-hexane:EtOH

= 1:1 at a flow rate of 0.5 mL/min for 5 and 7 or Chiralcel IC (5 µm, 150 4.6 mm) with n-

hexane:EtOH = 8:2 at a flow rate of 1.0 mL/min for 11-14. HPLC-UV and OR

chromatograms were measured with a Jasco MD-910 multiwavelength and OR-2090Plus

chiral detector, respectively. The baseline of the chromatograms were zeroed immediately

after the start of each run; this allowed the measurement of the relative absorbance or optical

rotation. The HPLC-ECD traces were recorded at the specified wavelength with a Jasco J-810

ECD spectropolarimeter equipped with a 1 cm path length HPLC flow cell and the baseline

was zeroed after the start of each run. The on-line ECD and UV spectra were recorded

simultaneously by stopping the flow at the UV absorption maximum of each peak. ECD

ellipticity values () were not corrected for concentration. For an HPLC-ECD spectrum, three

consecutive scans were recorded and averaged with 2 nm bandwidth, 1 s response, and

standard sensitivity. The HPLC-ECD spectrum of the eluent was recorded in the same way.

The concentration of the injected sample was set so that the HT (voltage) value did not exceed

500 V in the HT channel.

Plant Material. Matured fruits were purchased from the Metropolitan public market in

Panama City, Panama.

Extraction and Isolation: The pulp of red mamey (500 g) was homogenized in a

porcelain mortar with 50 g of NaHCO3 and extracted with acetone until the extract was

colorless. The extract was diluted with a mixture of Et2O/n-hexane (1:1), washed with H2O to

remove acetone, dried over Na2SO4, and evaporated to dryness. The residue was dissolved in

Et2O and saponified with methanolic KOH. After saponification, the ethereal solution was

washed with H2O and evaporated. The residue was subjected to open column chromatography

(Al2O3 Brokman grade III) using an increasing percentage of Et2O in n-hexane. Cryptocapsin-

5,6-epoxide (5), 3ʹ-deoxycapsanthin-5,6-epoxide (6) cryptoxanthin-5,6,5ʹ,6ʹ-diepoxide (8),

and cryptocapsin-5,8-epoxides (11, 12) were isolated in pure form by additional column

chromatography of Fraction 7 that was eluted with 50% Et2O in n-hexane. The purity of the

compounds was verified by HPLC-DAD.

Fraction 7 was subjected to open column chromatography (CaCO3 Biogal, Hungary,

toluene:n-hexane = 30:70). After development five fractions were visible: Fraction 71: 10 mm

brick red band (mixture of cryptocapsin-5,8-epoxides (11, 12) and 3ʹ-deoxycapsorubin17);

Fraction 72: 10 mm pink band: cryptocapsin-5,6-epoxide (5); Fraction 73: 20 mm red band

cryptocapsin (3); Fraction 74: 10 mm pink band 3ʹ-deoxycapsanthin-5,6-epoxide (6); and

Fraction 75: 3 mm yellow band cryptoxanthin-5,6,5ʹ,6ʹ-diepoxide (8).

After processing that consisted of cutting the column packing into sections and extracting

each section, Fractions 72-75 were obtained that were crystallized from benzene and n-hexane

yielding 4 mg of cryptocapsin-5,6-epoxide (5), 8 mg of cryptocapsin (3), 0,5 mg of 3ʹ-

deoxycapsanthin-5,6-epoxide (6), and 0.5 mg of cryptoxanthin 5,6,5ʹ,6ʹ-diepoxide (8).

The zone containing cryptocapsin-5,8-epoxides (11, 12) was subsequently subjected to a

second OCC separation (CaCO3 Biogal, Hungary, 4 % acetone in n-hexane). After

development, the following fractions were obtained: 5 mm red band (3ʹ-deoxycapsorubin), 7

mm yellow band (11, 12). After desorption the mixture of cryptocapsin-5,8-epoxides (11, 12)

was crystallized (benzene-n-hexane 1:10) to give 1.5 mg of red crystals.

Preparation of Semisynthetic Cryptocapsin-5,6-epoxides: To a solution of

cryptocapsin acetate (21 mg) in Et2O (80 mL) at room temperature, ca. 0.005 M

monoperoxyphthalic acid in Et2O (5 ml) was added. The mixture was kept under N2, in the

dark, and after 6 and 10 h, respectively, additional monoperoxyphthalic acid solution (5 and 8

mL) was added. After 20 h, the mixture was washed with 5% aq. NaHCO3 solution, the

organic phase was dried (Na2SO4), and a 30% KOH/MeOH solution (100 mL) was added.

After 16 h, the solution was washed with H2O until neutral, dried (Na2SO4), and evaporated.

Crystallization from benzene and n-hexane (ratio 1:10) yielded 5 mg of dark red crystals.

Preparation of Cryptocapsin-5,8-epoxides: To a solution of 3 mg of semisynthetic

cryptocapsin 5,6-epoxide (mixture of 5 and 7) in 50 mL of Et2O, 0.1 mL of HOAc-HCl (9:1)

solution were added at room temperature. The mixture was kept under N2 in the dark. The

reaction was monitored by UV-VIS. After 0.5 h, the mixture was diluted with Et2O, and

washed with 5% aqueous NaHCO3 solution, the Et2O phase was dried over Na2SO4, and

evaporated to dryness. The residue was crystallized from benzene and n-hexane (ratio 1:10),

yielding 2.5 mg of yellow crystals.

(5R,6S,3ʹS,5ʹR)-Cryptocapsin-5,6-epoxide ((5R,6S,3ʹS,5ʹR)-3ʹ-hydroxy-5,6-dihydro-

5,6-epoxy-,-caroten-6ʹ-one, 5): red crystals, mp. 136-137 oC, UV-VIS (benzene): max 480

and 505 (shoulder) nm, max after acid treatment: 464, 486 nm; 1H NMR (400 MHz, CDCl3)

0.84 (3H, s Me-16ʹ); 0.94 (3H, s Me-16); 1.04 (1H, dd, Hax-2); 1.10 (3H, s, Me-17), 1.15 (3H,

s Me-18); 1.21 (3H, s Me-17ʹ); 1.37 (3H, s, Me-18ʹ); 1.43 (1H, m, H-3); 1.49 (1H, dd, H ax-4ʹ,

Jgem = 14.5 Hz, J4ʹax,3ʹ = 3.1 Hz); 1.50 (1H, dd, Heq-2); 1.71 (1H, dd, Hax-2ʹ, Jgem=13.7 Hz,

J2ʹax,3ʹ=3.2 Hz); 1.72 (1H, dd, Hax-4); 1.89 (1H, dd, Heq-4); 1.94 (3H, s, Me-19); 1.96 (6H, s

Me-20,19ʹ); 1.98 (3H, s, Me-20ʹ); 2.00 (1H, dd, Heq-2ʹ, Jgem = 13.7 Hz, J2ʹeq,3ʹ = 7.8 Hz); 2.95

(1H, dd, Heq-4ʹ, Jgem = 14.5 Hz, J4ʹeq,3ʹ = 8.7 Hz); 4.51 (1H, m, H-3ʹ); 5.90 (1H, d, H-7, J7,8 =

15.4 Hz); 6.19 (1H, d, H-10, J10,11 = 11.3 Hz); 6.27 (1H, d, H-14); 6.29 (1H, d, J8,7 = 15.4 Hz);

6.34 (2H, m, H-8, H-14ʹ); 6.37 (1H, d, H-12, J12,11= 14.9 Hz); 6.44 (1H, d, H-7ʹ, J7ʹ,8ʹ = 15.1

Hz); 6.51 (1H, dd, H-12ʹ, J12ʹ,11ʹ = 14.6 Hz); 6.56 (1H, d, H-10ʹ, J10ʹ,11ʹ = 11.4 Hz); 6.61 (1H, d,

H-11ʹ, J11ʹ,10ʹ = 11.4 Hz); 6.63 (1H, d, H-11, J11,10 = 11.3 Hz); 6.65 (1H, m, H-15); 6.69 (1H, m,

H-15ʹ); 7.32 (1H, d, H-8ʹ, J8ʹ,7ʹ = 15.1 Hz); ECD n-hexane, [nm] (): 375 (0.46), 349

(3.45), 334sh (2.59), 321sh (1.10), 281 (8.05), 271sh (4.47), 242 (3.53), 226sh (1.42), 215

(5.88); HRESITOFMS: m/z 584.4240 (calcd. for C40H56O3, 584.4229).

Mixture of (5R,6S,3ʹS,5ʹR)-Cryptocapsin-5,6-epoxide (5) and (5S,6R,3ʹS,5ʹR)-

Cryptocapsin-5,6-epoxide (7): red crystals, UV-VIS (benzene): max 480 and 505 (shoulder)

nm, max after acid treatment: 464, 486 nm; 1H NMR (400 MHz, CDCl3): 0.84 (3H, s, Me-

16ʹ); 0.94 (3H, s, Me-17); 1.04 (1H, dd, Hax-2); 1.10 (3H, s, Me-16); 1.15 (3H, s, Me-18); 1.21

(3H, s, Me-17ʹ); 1.37 (3H, s, Me-18ʹ); 1.43 (1H, m, H-3); 1.49 (1H, dd, Hax-4ʹ, Jgem = 14.5 Hz,

J4ʹax,3ʹ = 3.1 Hz) 1.50 (1H, dd, Heq-2); 1.70 (1H, dd, Hax-2ʹ, Jgem = 13.7 Hz, J2ʹax,3ʹ = 3.2 Hz); 1.72

(1H, dd, Hax-4); 1.89 (1H, dd, Heq-4); 1.94 (3H, s, Me-19); 1.96 (3H, s, Me-19ʹ); 1.98 (6H, s,

Me-20, 20ʹ); 2.00 (1H, dd, Heq-2ʹ, Jgem = 13.7 Hz, J2ʹeq,3ʹ = 7.8 Hz); 2.95 (1H, dd, Heq-4ʹ, Jgem =

14.5 Hz, J4ʹeq,3ʹ = 8.7 Hz); 4.51 (1H, m, H-3ʹ); 5.90 (1H, d, H-7, J7,8 = 15.4 Hz), 6.19 (1H, d, H-

10, J10,11 = 11.3 Hz); 6.27 (1H, d, H-14); 6.29 (1H, d, H-8, J8,7 = 15.4 Hz); 6.34 (1H, d, H-14ʹ);

6.37 (1H, d, H-12, J12,11 = 14.9 Hz); 6.44 (1H, d, H-7ʹ, J7ʹ,8ʹ = 15.1 Hz); 6.51 (1H, d, H-12ʹ,

J12ʹ,11ʹ = 14.6 Hz), 6.56 (1H, d, H-10ʹ, J10ʹ,11ʹ = 11.4 Hz); 6.61 (1H, dd, H-11ʹ, J11ʹ,10ʹ = 11.4 Hz);

6.63 (1H, d, H-11); 6.65 (1H, m, H-15); 6.69 (1H, m, H-15ʹ); 7.32 (1H, d, H-8ʹ , J7ʹ,8ʹ = 15.1

Hz); 13C NMR (100 MHz, CDCl3): 12.7 (C-20); 12.8 (C-20ʹ,19); 13.0 (C-19ʹ); 17.10 (C-3);

21.1 (C-18); 21.3 (C-18ʹ); 25.1 (C-17ʹ); 25.9 (C-16ʹ,17); 26.0 (C-16); 30.1 (C-4); 33.83 (C-1);

35.8 (C-2); 44.0 (C-1ʹ); 45.3 (C-4ʹ); 50.9 (C-2ʹ); 58.93 (C-5ʹ); 65.5 (C-5); 70.4 (C-3ʹ); 71.4 (C-

6); 120.90 (C-7ʹ); 124.1 (C-11ʹ); 124.4 (C-7); 125.33 (C-11); 129.8 (C-15); 131.6 (C-15ʹ);

131. 8 (C-10); 132.5 (C-14); 133.6 (C-9ʹ); 134.9 (C-9); 135.2 (C-14ʹ); 136.0 (C-13); 137.2 (C-

8); 137.5 (C-13ʹ); 137.8 (C-12); 140.7 (C-10ʹ); 141.9 (C-12ʹ); 146.8 (C-8ʹ); 202.9 (C-6ʹ);

HRESITOFMS: m/z 584.4246 (calcd. for C40H56O3, 584.4229); 5: tr= 31.0 min; 7: tr= 43.1

min on Chiralcel OD column (0.46 cm 25 cm, 5 m) with n-hexane/EtOH 1:1 and a flow

rate 0.5 mL/min.

7: HPLC-ECD n-hexane/EtOH 1:1, [nm] (): 351 (0.91), 321sh (0.34), 282 (3.89),

268sh (1.81), 251sh (0.63), 231 (2.16), 208 (24.98).

5: HPLC-ECD n-hexane/EtOH 1:1, [nm] (): 385 (0.15), 353 (1.06), 339sh (0.96),

324sh (0.47), 283 (2.96), 271sh (1.65), 242 (1.09), 215 (2.45).

3ʹ-Deoxycapsanthin-5,6-epoxide ((3S,5S,6R,5ʹR)-3-hydroxy-5,6-dihydro-5,6-epoxy-

,-caroten-6ʹ-one, 6): red crystals UV-VIS (benzene): max 481 and 504 (shoulder) nm, max

after acid treatment: 463, 485 nm; 1H NMR (500 MHz, CDCl3): 0.85 (3H, s, Me-16ʹ); 0.98

(3H, s, Me-17); 1.11 (3H, s, Me-17ʹ); 1.16 (3H, s, Me-16); 1.19 (3H, s, Me-18); 1.27 (1H, dd,

Hax-2, J2ax,3 = 10.2 Hz), 1.30 (3H, s Me-18ʹ); 1.50 (1H, dd, Hax-4ʹ), 1.57 (1H, dd, Heq-2ʹ); 1.62

(1H, ddd, Heq-2, Jgem=14.7 Hz, J2eq.,3 =3.6 Hz, J2eq.,4 =1.7 Hz), 1.65 (1H, dd, Hax-4, Jgem= 14.2

Hz, J4ax.3 = 8.8 Hz); 1.68 (1H, dd, Hax-2ʹ); 1.70 (1H, m, H-3ʹ); 1.93 (1H, s, Me-19); 1.97 (3H,

s, Me-19ʹ), 1.98 (6H, s, Me-20, 20ʹ); 2.36 (1H, dd, Heq-4); 2.55 (1H, dd, Heq-4ʹ); 3.93 (1H, m,

H-3), 5.92 (1H, d, H-7, J7,8 = 15.5 Hz); 6.20 (1H, d, H-10, J10,11 = 11.5 Hz); 6.26 (1H, H-14);

6.29 (1H, d, H-8, J7,8 = 15.5 Hz); 6.34 (1H, d, H-14ʹ); 6.36 (1H, d, H-12, J11,12 = 13 Hz); 6.48

(1H, d, H-7ʹ, J7ʹ,8ʹ = 15 Hz); 6.51 (1H, d, H-12ʹ, J11ʹ,12ʹ = 14.5 Hz); 6.57 (1H, d, H-10ʹ, J10ʹ,11ʹ =

11.3 Hz); 6.59 (1H, dd, H-11); 6.63 (1H, dd, H-11ʹ); 6.64 (1H, m, H-15); 6.67 (1H, m, H-15ʹ);

7.32 (1H, d, H-C8ʹ, J7ʹ,8ʹ = 15 Hz); ECD n-hexane, [nm] (): 365 (0.14), 347 (2.32),

332sh (1.69), 315sh (0.48), 280 (6.35), 270sh (3.64), 240 (2.52), 233sh (0.78), 214 (4.10).

HR ESI-TOF MS: m/z 584.4231 (calcd. for C40H56O3, 584.4229).

(3S,5R,6S,5ʹR,6ʹS)--Cryptoxanthin-5,6,5ʹ,6ʹ-diepoxide ((3S,5R,6S,5ʹR,6ʹS)-3-

hydroxy-5,6,5ʹ,6ʹ-tetrahydro-5,6,5ʹ,6ʹ-diepoxy--caroten-3-ol, 8) orange crystals, mp.

148-150 oC, UV-VIS (benzene): max 428, 453, and 483 nm, max after acid treatment: 388,

410, 436 nm; 1H NMR (500 MHz, CDCl3): 0.95 (3H, s, Me-16ʹ); 0.98 (3H, s, Me-16); 1.08

(1H, m, H-2ʹ); 1.11 (3H, s, Me-17ʹ); 1.15 (3H, s, Me-17); 1.16 (3H, s, Me-18ʹ); 1.19 (3H, s,

Me-18); 1.42 (1H, m, H-3ʹ); 1.47 (1H, m, H-2ʹ); 1.75 (1H, m, H-4ʹ); 1.90 (1H, m, H-4ʹ); 1.94

(6H, s, Me-19,19ʹ); 1.97 (6H, s, Me-20,20ʹ); 1.26 (1H, m, H-2ax); 1.57 (1H, m, H-2eq); 1.64

(1H, m, H-4ax); 2.40 (1H, m, H-4eq); 3.92 (1H, m, H-3ax); 5.88 (1H, d, H-7, J7,8 = 15.4 Hz),

6.20 (2H, d, H-10,10ʹ); 6.27 (1H, d, H-8); 6.29 (2H, d, H-14,14ʹ); 6.36 (2H, d, H-12,12ʹ, J12,11

= 15 Hz); 6.60 (2H, d, H-11,11ʹ, J11,10 = 11 Hz), 6.63 (2H, dd, H-15,15ʹ); ECD n-hexane,

[nm] (): 355 (0.17), 327 (1.57), 312sh (0.81), 266 (10.04), 255sh (4.72), 230 (2.72),

208 (5.05); HR ESI-TOF MS: m/z 584.4214 (calcd. for C40H56O3, 584.4229).

Mixture of (5R,8S,3S,5ʹR)-Cryptocapsin-5,8-epoxide (11) and (5R,8R,3ʹS,5ʹR)-

Cryptocapsin-5,8-epoxide (12): orange crystals, UV-VIS (benzene): max 464, 486 nm;

HRESITOFMS: m/z 584.4301 (calcd. for C40H56O3, 584.4229). tr= 14.3 min for 11 and 19.0

min for 12 on Chiralcel IC (5 µm, 150 4.6 mm) with n-hexane/EtOH 8:2 and a flow rate of

1.0 mL/min.

(5R,8S,3ʹS,5ʹR)-Cryptocapsin-5,8-epoxide ((5R,8S,3ʹS,5ʹR)-3ʹ-hydroxy-5,6-dihydro-

5,8-epoxy-,-caroten-6ʹ-one, 11)

1H NMR (500 MHz, CDCl3) 0.84 (3H, s, Me-16ʹ), 1.12 (3H, s Me-16)b, 1.19 (3H, s, Me-

17)b, 1.22 (3H, s Me-17ʹ), 1.38 (3H, s Me-18ʹ), 1.48 (3H, s Me-18), 1.49 (1H, dd, H ax-C4ʹ,

Jgem=14.5 Hz, J4ʹax,3ʹ=3.1 Hz), 1.71 (1H, dd, Hax-2ʹ, Jgem = 13.7 Hz, J2ʹax,3ʹ = 3.2 Hz), 1.81 (3H, s,

Me-19); 1.96 (3H, s, Me-19ʹ); 1.98 (6H, s, Me-20,20ʹ); 2.02 (1H, dd, Heq-2ʹ, Jgem = 13.7 Hz,

J2ʹeq,3ʹ = 7.8 Hz); 2.95 (1H, dd, Heq-4ʹ, Jgem = 14.5 Hz, J4ʹeq,3ʹ = 8.7 Hz); 4.51 (1H, m, H-3ʹ); 5.07

(1H, br. s, H-8, J7,8 ~ 1.7 Hz); 5.24 (1H, d, H-7); 6.19 (1H, d, H-10, J10,11 = 11.2 Hz), 6.23 (1H,

d, H-14, J14,15 = 11.4 Hz); 6.32 (1H, d, H-12); 6.34 (1H, d, H-14ʹ); 6.46 (1H, d, H-7ʹ, J7ʹ,8ʹ =

15.1 Hz), 6.51 (1H, dd, H-11, J11,10 = 15.0 Hz); 6.53 (1H, d, H-12ʹ, J12ʹ,11ʹ = 14.6 Hz), 6.57 (1H,

d, H-10ʹ, J10ʹ,11ʹ = 11.2 Hz); 6.62 (1H, dd, H-11ʹ); 6.64 (1H, m, H-15); 6.70 (1H, m, H-15ʹ);

7.32 (1H, d, H-8ʹ, J8ʹ,7ʹ = 15.1 Hz); 13C NMR (125 MHz, CDCl3): 12.5 (C-19); 12.9 (C-

20ʹ)a; 13.0 (C-19ʹ,20)b; 20.3 (C-3); 21.3 (C-18ʹ); 25.1 (C-17ʹ); 25.8 (C-16); 25.9 (C-16ʹ); 25.9

(C-18); 30.6 (C-17); 41.2 (C-4); 41.4 (C-2); 45.3 (C-4ʹ); 50.9 (C-2ʹ); 70.4 (C-3ʹ); 87.7 (C-8);

117.6 (C-7); 120.9 (C-7ʹ), 124.2 (C-11ʹ), 126.8 (C-10); 131.7 (C-15ʹ), 134.9 (C-14ʹ), 140.7 (C-

10ʹ), 141.9 (C-12ʹ), 146.8 (C8ʹ). HPLC-ECD n-hexane/EtOH 8:2, [nm] (): 376 (0.87),

330 (2.82), 321sh (2.63), 282sh (0.68), 267 (3.73), 229sh (2.55), 204 (12.22).

(5R,8R,3ʹS,5ʹR)-Cryptocapsin-5,8-epoxide ((5R,8R,3ʹS,5ʹR)-3ʹ-hydroxy-5,6-dihydro-

5,8-epoxy-,-caroten-6ʹ-one, 12)

1H NMR (500 MHz, CDCl3) 0.84 (3H, s, Me-16ʹ), 1.11 (3H, s, Me-16)a, 1.16 (3H, s, Me-

17)a, 1.22 (3H, s, Me-17ʹ); 1.25 (1H, m, Hax-2); 1.38 (3H, s, Me-18ʹ), 1.44 (3H, s, Me-18),

1.49 (1H, dd, Hax-4ʹ, Jgem = 14.5 Hz, J4ʹax,3ʹ = 3.1 Hz), 1.59 (1H, m, Heq-2); 1.61 (1H, m, Hax-4);

1.65 (1H, m, H-3); 1.71 (1H, dd, Hax-2ʹ, Jgem = 13.6 Hz); 1.76 (3H, s, Me-19); 1.96 (3H, s, Me-

19ʹ); 1.98 (6H, s, Me- 20,20ʹ); 2.01 (1H, m, Heq-4); 2.02 (1H, dd, Heq-2ʹ, J2ʹeq,3ʹ = 8.1 Hz); 2.95

(1H, dd, Heq-4ʹ, J4ʹeq,3ʹ = 8.5 Hz); 4.51 (1H, m, H-3ʹ); 5.16 (1H, d, H-7, J7,8<1 Hz); 5.18 (1H, d,

H-8); 6.20 (1H, d, H-10, J10,11 = 11.4 Hz); 6.23 (1H, d, H-14, J14,15 = 11.4 Hz); 6.32 (1H, d, H-

12, J12,11 = 15 Hz), 6.34 (1H, d, H-14ʹ); 6.46 (1H, d, H-7ʹ, J7ʹ,8ʹ = 15.1 Hz); 6.51 (1H, dd, H-11,

J11,10 = 15.0 Hz); 6.53 (1H, dd, H-12ʹ, J12ʹ,11ʹ = 14.6 Hz); 6.57 (1H, d, H-10ʹ, J10ʹ,11ʹ = 11.4 Hz);

6.62 (1H, dd, H-11ʹ); 6.64 (1H, m, H-15); 6.70 (1H, m, H-15ʹ); 7.32 (1H, d, H-8ʹ, J8ʹ,7ʹ = 15.1

Hz); 13C NMR (125 MHz, CDCl3): 12.5 (C-19); 12.9 (C-20ʹ)a; 13.0 (C-19ʹ, 20)b; 20.3 (C-

3); 21.3 (C-18ʹ); 25.1 (C-17ʹ); 25.8 (C-16); 25.9 (C-16ʹ); 25.9 (C-18); 30.6 (C-17); 41.2 (C-4);

41.4 (C-2); 45.3 (C-4ʹ); 50.9 (C-2ʹ); 70.4 (C-3ʹ); 87.1 (C-8); 118.7 (C-7); 120.9 (C-7ʹ); 124.2

(C-11ʹ); 126.8 (C-10); 131.6 (C-15ʹ); 134.9 (C-14ʹ); 140.7 (C-10ʹ); 141.9 (C-12ʹ); 146.8 (C-

8ʹ). HPLC-ECD n-hexane/EtOH 8:2, [nm] (): 395 (0.13), 373sh (0.68), 348 (1.29),

265 (7.73), 234sh (3.14), 205 (18.85).

(5S,8R,3ʹS,5ʹR)-Cryptocapsin-5,8-epoxide ((5S,8R,3ʹS,5ʹR)-3ʹ-hydroxy-5,6-dihydro-

5,8-epoxy-,-caroten-6ʹ-one, 13)

tr= 15.8 min on Chiralcel IC (5 µm, 150 4.6 mm) with n-hexane/EtOH 8:2 and a flow rate of

1.0 mL/min. HPLC-ECD n-hexane/EtOH 8:2, [nm] (): 391 (0.21), 367sh (0.30), 354

(0.41), 325 (0.61), 265sh (2.36), 258 (2.37), 234sh (1.79), 205 (7.98).

(5S,8S,3ʹS,5ʹR)-Cryptocapsin-5,8-epoxide ((5S,8S,3ʹS,5ʹR)-3ʹ-hydroxy-5,6-dihydro-

5,8-epoxy-,-caroten-6ʹ-one, 14)

tr= 17.2 min on Chiralcel IC (5 µm, 150 4.6 mm) with n-hexane/EtOH 8:2 and a flow rate of

1.0 mL/min. HPLC-ECD n-hexane/EtOH 8:2, [nm] (): 364 (0.85), 331 (5.35), 321sh

(4.78), 306sh (2.12), 284sh (0.58), 267 (7.54), 233sh (2.24), 204 (18.44).

ASSOCIATED CONTENT

Supporting Information

1D and 2D NMR spectra for compounds 5-11. Supplementary data associated with this article

are available free of charge via the Internet at http://pubs.acs.org.

AUTHOR INFORMATION

Corresponding author Tel.: +36-72-536356; fax: +36-72-536225; e-mail:jozsef.deli@aok.pte.hu

ACKNOWLEDGEMENTS

This study was supported by the grants OTKA K 83898, K 105871, K 105459 (Hungarian

National Research Foundation) and SENACYT (Secretaria Nacional de Ciencia y Tecnología

de Panamá). The work is supported by the TÁMOP-4.2.2.A-11/1/KONV-2012-0025 and the

TÁMOP/SROP-4.2.2/B-10/1-2010-0029 projects. The projects are co-financed by the

European Union and the European Social Fund. The authors thank Ms. Zs. Götz, Mrs. J. Rigó

and Mr. N. Götz for their skillful assistance.

DEDICATION

This article is dedicated to the memory of late Prof. Hans Conrad Eugster (17.07.1921 –

21.08.2012).

REFERENCES

(1) Zechmeister, L.; Cholnoky, L. Justus Liebigs. Ann. Chem. 1927, 454, 54-71.

(2) Deli, J.; Molnár, P. Curr. Org. Chem. 2002, 6, 1197-1219.

(3) Deli, J.; Matus, Z.; Tóth, G. Z. Lebensm. Unters. Forsch. A 1997, 205, 388-391.

(4) Karrer, P.; Oswald, A. Helv. Chim. Acta 1935, 18, 1303-1305.

(5) Deli, J.; Molnár, P.; Matus, Z.; Tóth, G.; Steck, A.; Pfander, H. Chromatographia 1998,

48, 27-31.

(6) Bubicz, M. Bull. Acad. Polon. Sci. Ser. Sci. Biol. 1965, 13, 251-255.

(7) Simpson, D. J.; Baqar, M. R.; Lee, T. H. Ann. Bot. 1977, 41, 1101-1107.

(8) Deli, J.; Matus, Z.; Tóth, G. J. Agr. Food Chem. 2000, 48, 2793-2796.

(9) Seybold, . A. Sber. Heidelb. Akad. Wiss. Math.-Naturwiss. Kl. 1953, 4, 31-124.

(10) Parkes, K. E. B.; Pattenden, G.; Baranyai, M.; Molnár, P.; Szabolcs, J.; Tóth, G.

Tetrahedron Lett. 1986, 27, 2535-2538.

(11) Deli, J.; Molnár, P.; Matus, Z.; Tóth, G.; Steck, A. Helv. Chim. Acta 1996, 79, 1435-

1443

(12) Deli, J.; Molnár, P.; Matus, Z.; Tóth, G.; Steck, A.; Pfander, H. Helv. Chim. Acta

1998, 81, 1233-1241.

(13) Deli, J.; Molnár, P.; Ősz, E.; Tóth, G. Tetrahedron Letters 2000, 41, 8153-8155.

(14) Maoka, T.; Akimoto, N.; Fujiwara, Y.; Hashimoto, K. J. Nat. Prod. 2004, 67, 115-117.

(15) Murillo, E.; Watts, M.; Mosquera, V.; Robinson, J.; McLean, R. Acta Biol. Cracov.

2011, 53 (Suppl. 1) 61.

(16) Murillo, E.; McLean, R.; Britton, G.; Agócs, A.; Nagy, V.; Deli, J. J. Nat. Prod. 2011,

74, 283-285.

(17) Murillo, E.; Mosquera, Y.; Kurtán, T.; Gulyás-Fekete, G.; Nagy, V.; Deli, J. Helv.

Chim. Acta 2012, 95, 983-988.

(18) Deli, J.; Turcsi, E.; Szabó, I.; Mosquera, Y.; Murillo, E. Acta Biol. Cracov. 2011, 53

(Suppl. 1) 55.

(19) Molnár, P.; Deli, J.; Matus, Z.; Tóth, G.; Steck, A.; Pfander, H. Helv. Chim. Acta 1997,

80, 221-229.

(20) Deli, J.; Molnár, P.; Matus, Z.; Tóth, G.; Steck, A.; Pfander, H. Helv. Chim. Acta 1998,

81, 1242-1253.

(21) Buchecker, R.; Noack, K. Circular Dichroism. In Carotenoids Vol. 1B. Spectroscopy,

Britton, G. Liaaen-Jensen, S. Pfander, H. Eds. Birkhäuser: Basel, 1995; pp. 63–116.

(22) Dai, J.; Krohn, K.; Flörke, U.; Draeger, S.; Schulz, B.; Kiss-Szikszai, A.; Antus, S.;

Kurtán, T.; van Ree, T. Eur. J. Org. Chem. 2006, 3498-3506.

(23) Yao, S.; Tang, C.-P.; Ye, Y.; Kurtán, T.; Kiss-Szikszai, A.; Antus S.; Pescitelli, G.;

Salvadori, P.; Krohn, K. Tetrahedron: Asymmetry 2008, 19, 2007-2014.

(24) Bringmann, G.; Götz, D.; Bruhn, T. in: Comprehensive Chiroptical Spectroscopy

(Eds.: Berova, N.; Polavarapu, P. L.; Nakanishi, K.; Woody R. W.), John Wiley & Sons,

Hoboken, 2012, vol. 2, pp. 355-420.

(25) Englert, G. NMR Spectroscopy. In Carotenoids Vol. 1B. Spectroscopy, Eds. Britton,

G.; Liaaen-Jensen,; S. Pfander, H. Birkhäuser Verlag, Basel, 1995, pp. 147 - 260.

(26) Acemoglu, M.; Prewo, R.J.; Bieri, H.; Eugster, C. H. Helv. Chim. Acta 1984, 67, 175-

183.

(27) Eugster, C. H. Pure Appl. Chem. 1985, 57, 639-647.

(28) Eschenmoser, W.; Marki-Fischer, E.; Eugster, C. H. Helv. Chim. Acta 1984, 67, 170-

174.

(29) Bouvier, F.; Hugueney, P.; dʹHarlingue, A.; Kuntz, M.; Camara, B. Plant J. 1994, 6,

45-54.

Structures:

O

HO

OH

OO

OH

OH

Capsorubin (2)

Capsanthin (1)

O

OH

Cryptocapsin (3)

O

Sapotexanthin (4)

1

2

3

4

5

6

7 1'

2'

3'

4'

5'6'

7'

1

2

3

4

5

6

7

O

OH

O

OO

HO

(5R,6S)-Cryptocapsin-5,6-epoxide (5 )

3'-Deoxycapsanthin-5,6-epoxide (6)

O

OH

HO

(5S ,6R)-Cryptocapsin-5,6-epoxide (7 )

(3S,5R,6S,5'R,6'S)-ß-Cryptoxanthin-5 ,6,5',6'-diepoxide (8)

O

O

O

HO

(3R,5'R,6 'S )-ß-Cryptoxanthin-5',6'-epoxide (9)

O

O

OH

(3S ,5R,6S)-Capsanthin-5,6-epoxide (10)HO

O

O

OH

(5R,8S)-Cryptocapsin-5,8-epoxide (11)

O

O

OH

(5R,8R)-Cryptocapsin-5,8-epoxide (12)

O

O

OH

(5S,8R)-Cryptocapsin-5,8-epoxide (13)

O

O

OH

(5S ,8S )-Cryptocapsin-5,8-epoxide (14)

O

Figures:

200 300 400

-30

-20

-10

0

10C

D[m

de

g]

Wavelegth[nm]

Figure 1. ECD spectra of (5R,6S,3ʹS,5ʹR)-cryptocapsin-5,6-epoxide (5, red) (3R,5R,6S,5ʹR)-3ʹ-deoxycapsanthin-5,6-epoxide (6, blue) and (3S,5R,6S,5ʹR,6ʹS)--cryptoxanthin-5,6,5ʹ,6ʹ-diepoxide (8, black).

20 25 30 35 40 45 50

HPLC-UV (PDA)

HPLC-OR (chiral detector)

5x104

105

V

AU

retention time (min)

0

500

1500 1800 2100 2400 2700 3000

-9

-6

-3

0

3

300

310

320

330

340

350HPLC-CD (J-810)

HPLC-UV (J-810)

V)

mdeg)

retention time (s)

Figure 2. a) HPLC-UV (upper blue curve) and -OR (lower red curve) chromatograms of the separated (5R,6S,3ʹS,5ʹR)- and (5S,6R,3ʹS,5ʹR)-cryptocapsin-5,6-epoxide diastereomers (5, 7) monitored at 480 nm (Chiralcel OD, n-hexane/EtOH 50:50). b) HPLC-ECD (upper blue curve) and –UV (lower red curve) chromatograms of the separated (5R,6S,3ʹS,5ʹR)- and (5S,6R,3ʹS,5ʹR)-cryptocapsin-5,6-epoxide diastereomers monitored at 280 nm with J-810 spectropolarimeter (Chiralcel OD, n-hexane/EtOH 50:50).

225 250 275 300 325 350 375 400

-3

-2

-1

0

1

2

3

4

mde

g

wavelength (nm)

Figure 3. HPLC-ECD spectra of (5R,6S,3ʹS,5ʹR)–cryptocapsin-5,6-epoxide (5, red, first-eluting distereomer) and (5S,6R,3ʹS,5ʹR)-cryptocapsin-5,6-epoxide (7, blue, second-eluting diastereomer).

10 12 14 16 18 20 220,0

5,0x104

1,0x105

1,5x105

2,0x105

2,5x105

3,0x105

3,5x105

4,0x105

ab

sorb

an

ce (

mA

U)

retention time [min]

(5R,8S )-11(5R,8R)-12

(5S,8S )-14

(5S,8R)-13

Figure 4. Overlapped HPLC-UV traces (463 nm) of natural [blue, (5R,8S,3ʹS,5ʹR)-11, (5R,8R,3ʹS,5ʹR)-12] and semisynthetic stereoisomeric mixture of cryptocapsin-5,8-epoxides [red, (5R,8S,3ʹS,5ʹR)-11, (5R,8R,3ʹS,5ʹR)-12, (5S,8R,3ʹS,5ʹR)-13, (5S,8S,3ʹS,5ʹR)-14] with Chiralpak IC column (n-hexane/EtOH 80:20);

200 225 250 275 300 325 350 375 400-20

-15

-10

-5

0

5

10

15

20

[m

de

g]

wavelegth[nm]

Figure 5. HPLC-ECD spectra of diastereomeric cryptocapsin-5,8-epoxides in n-hexane/EtOH 80:20: black: (5R8S,3ʹS,5ʹR)-11, first-eluting; red: (5S8S,3ʹS,5ʹR)-14, second-eluting; blue: (5S8R,3ʹS,5ʹR)-13, third-eluting; brown: (5R8R,3ʹS,5ʹR)-12, fourth-eluting diastereomer.

Schemes:

HOß-Cryptoxanthin-5,6,5',6'-diepoxide

O

O

O

OH

Cryptocapsin-5,6-epoxide

OO

3'-Deoxycapsanthin-5,6-epoxide

O

HO

Scheme. 1. Formation of cryptocapsin-5,6-epoxide (5) and 3ʹ-deoxycapsanthin-5,6-epoxide (6) from -cryptoxanthin-5,6,5ʹ,6ʹ-diepoxide (8)

For the Table of contents:

O

OH

O

OO

HO

(5R,6S) -Cryptocapsin-5,6-epoxide

3'-Deoxycapsanthin-5,6-epoxide